A phase 1 trial with immunotoxin BL22 that targets CD22 on B cell malignancies has been completed and a maximum tolerated dose established as 40 micrg/kg given I.V. every other day for 3 doses. The therapeutic responses in this trial were extraordinary with more than half the patients with drug resistant Hairy Cell Leukemia going into complete remission. A phase 2 trial in HCL has been approved and is open to accrual. A phase 1 trial with BL22 in pediatric malignancies in collaboration with D. Alan Wayne has been planned and should open soon. Two phase 1 trials with immunotoxin SS1P that targets ovarian cancers, mesotheliomas and pancreatic cancers are now open. In one trial SS1P is given continuously for 10 days. In the other trial SS1P is given by bolus injection every other day times three. Several minor responses but no major responses have been observed. The MTD has not yet been reached. Phase 2 trials with LMB2, an immunotoxin targeting CD25 have also been planned in patients with CLL and CTCL and should be open late in 2003.